C-Reading: Claims: Credibility

C-Reading: Claims: Credibility

C-reading: Claims: Credibility

(Moore & Parker, 84-107)

We size up people's believability, or credibility, every day. Sometimes we make mistakes.

On July 13, 2002, Charles Keller of Sacramento, California, withdrew $10,000 from his Wells Fargo savings account and gave it to two men he didn't know from Adam. The men had convinced Keller, merely by talking to him for a while, that by giving them $10,000 to demonstrate "good faith" he would receive a check for $60,000 at the end of the day. They told Mr. Keller they represented an organization that located individuals who had received large inheritances but didn't know it and were authorized to pay “finder’s fees” to anyone who could help them locate the people. We don't know for sure what else they told Mr. Keller, but it is easy to imagine possibilities. Perhaps they described a neighbor of Mr. Keller as one of the people they were looking for, prompting Keller to think the finder’s fee would be easy money.

It may strike you as odd that anyone at least smart enough to accumulate $10,000 in the bank would fall for such an obvious swindle. Yet people both wealthy and intelligent are conned every day. I’d bet in your own neighborhood there are intelligent people who are losing their shirt at this very moment. The problem stems not from a lack of intelligence but from other things, including perhaps wishful thinking; it also stems from a failure to judge credibility correctly.

Two different things in varying degrees have or lack credibility: claims and sources (that is, people). Some claims lack credibility no matter who says them; other claims depend for their credibility on who says them.

Do ducks quack in Morse Code? The idea would lack credibility no matter who were to express it. But the claim that ducks mate for life would depend for its credibility on who said it. It would be more believable coming from a bird expert than from me, for example.

Credibility is not an all-or-nothing thing, whether we are talking about claims or sources. If someone claimed that George W. Bush sends weekly bribes to the U.S. Supreme Court, his claim would be rather far-fetched. But it wouldn’t be as far-fetched as the claim that George W. Bush is a space alien. A similar variability in credibility attaches to people. An individual known to lie habitually is less credible than an honest person. A man charged with armed robbery becomes less credible in his denial if we learn he owns a silencer and an illegal semi-automatic handgun with the serial numbers removed.

Now, we often judge the credibility of people on the basis of irrelevant considerations. Physical characteristics, for instance, are poor indicators of credibility or its lack. Does a person maintain eye contact? (Mr. Keller's swindlers might well have.) Is the person sweating? Does he or she laugh nervously? Does he or she shake our hand firmly? These characteristics are widely used in sizing up a person’s credibility. But they are generally worthless. Studies show there are other irrelevant features we sometimes use to judge a person’s credibility, like gender, height, age, ethnicity, accent, and mannerisms. People also make credibility judgments on the basis of the clothes a person wears. A person’s occupation certainly bears a relationship to his or her knowledge or abilities, but as a guide to moral character or truthfulness, it is not always reliable (well, unless you are talking about people with jobs as lawyers, advertisers, real estate agents, or with the media…no, a car salesman didn’t make the list, because they are known to sprinkle in some truth and people are savvy enough to be on the look out for their lies). You may have the idea that you can size up a person just by looking into his or her eyes (President Bush said he could tell Russia’s Putin had a good soul just by looking into his eyes. Check into Putin’s record on human rights and democratization since then…. I guess Bush’s “soul” vision glasses were on the fritz that day… although Bush’s record on human rights and democratization is looking a little shabby, so maybe he meant something else by “good soul” than what I would mean). This is a mistake. Just by looking at someone we cannot ascertain that person's truthfulness, knowledge, or character.

We need to ask two questions: When does a claim lack credibility inherently - in other words, when does a claim’s content lack credibility? And when does a claim’s source lack credibility?


A claim lacks inherent credibility to the extent it conflicts with our “General Understanding of Stuff”.

Our G.U.S. (General Understanding of Stuff) is a topic in its own right. G.U.S. is all of the competencies we carry around with us. It is “general understanding” because it goes far beyond what we would normally call knowledge, and we may not be able to specify where we learned it, unlike something we know because we witnessed it this morning. Much of our background information is well confirmed by a variety of sources, but we would most often be hard-pressed to list those sources from memory. Our G.U.S. includes things like experiences, techniques, things we have learned, things we’ve heard, etc. Some of you might not feel very smart, such as you may struggle to answer a single question on Jeopardy, but the amount of information and competence that all of us rely on even to do the most mundane tasks is astounding. Just think of what kind of intellectual work is going on in you brain as you read this. Tying your shoes, driving your car, or using a computer requires an immense amount of knowledge, experience, and know-how. Much of this content is shared by most of us that are reading this. For example, we can pretty much rely on the fact that everyone in this class shares a certain level of competence with understanding spoken and written English. Too many people these days exaggerate the differences between people, because even the simple act of being able to communicate with one another shows an incredible commonality of backgrounds and expectations. But, of course, over and above the vast amounts of shared G.U.S., we do have different sets of experiences and knowledge that we can rely on for judging the claims made by others. I’m assuming that I have far more G.U.S. concerning things like philosophy, logic, and, say, surfing, than most of you, because I’ve spent many years acquiring knowledge and experience at those things. Most of you, by contrast, likely have far more G.U.S. than I do in areas like cell phones (I refuse to own one), hair care products (again, I refuse), television shows (yawn), or cars (I don’t worship shiny objects like you do, you necrophiliacs). Jokes aside, we will likely be shocked to find that some members of our class have very technical expertise in quite astounding things.

It is therefore only reasonable to be suspicious of any claim that comes into conflict with what we know. Factual claims must always be evaluated against our G.U.S. Factual claims that conflict with this store of information are usually quite properly dismissed, even if we cannot disprove them through direct observation. We immediately reject the claim “Palm trees grow in abundance near the North Pole,” even though we are not in a position to confirm or disprove the statement by direct observation. Indeed, this is an example of how we usually treat claims when we first encounter them: We begin by assigning them a certain initial plausibility, a rough assessment of how believable a claim seems to us. This assessment depends on how consistent the claim is with our background information - how well it “fits” with that information. If it fits very well, we give the claim a high degree of initial plausibility, and, thus, we lean toward accepting it. If, however, the claim conflicts with our background information, we give it low initial plausibility and lean toward rejecting it unless very strong evidence can be produced on its behalf. The claim “More guitars were sold in the United States last year than saxophones” fits very well with the background information most of us share, and we would hardly require detailed evidence before accepting it. However, the claim “Charlie's eighty-seven-year-old grandmother swam across Lake Michigan in the middle of winter” cannot command much initial plausibility because of the obvious way it conflicts with our background information about eighty-seven-year-old people, about the size and temperature of Lake Michigan, about swimming in cold water, and so on. In fact, short of observing the swim ourselves, it isn't clear just what could persuade us to accept such a claim.

Unfortunately, there are no neat formulas that can resolve conflicts between what you already believe and new information. Your job as a critical thinker is to trust your background information when considering claims that conflict with that information - that is, claims that you judge to have low initial plausibility - but at the same time to keep an open mind and realize that further information may cause you to give up a claim you had thought was true. After all, many of the things you think you know come from questionable sources, such as anything you hear from TV. It’s a difficult balance, but it’s worth getting right.

Let's take a common sort of example from my life. I have become quite interested in politics in recent years, especially in areas like U.S foreign policy and health care. As such, sadly, I have quite a bit more knowledge about these things than the average citizen. Here is a true story. One day in a biomedical ethics class discussion about the expense of universal health care a student remarked, “You know we spend more on welfare than defense in this country.” Now, because of my special G.U.S. on this topic and this particular issue, I knew right away that her claim could not have been more false. In fact, due to my background knowledge, the initial plausibility of her claim, based on my special G.U.S. was nearly zero. I had just been studying the official U.S budget documents, so I was quickly able to correct her misunderstanding. Someone without this G.U.S. might have found her claim believable until (I can only dream) they went and checked the numbers for themselves. (By the way, in case you are curious, we currently spend at least twenty five times more on defense than welfare, over $420 billion dollars more.)


A source lacks credibility to the extent that she is unlikely to have access to the information or shows signs in her character or coercion that she is being dishonest.

A person may lack credibility in various ways, but most of them relate either to (1) his or her expertise or (2) his or her sincerity. If we believe the source may be lacking in knowledge, experience, or access on the particular issue being addressed, then we have a reason for concern under criterion (1). If we have reason to think a source may be biased or self-serving about a subject, or for other reasons may not be giving us a full and complete and impartial report, then we have a reason for concern under criterion (2). Generally speaking, it's reasonable to accept a claim from a credible source if it does not conflict with your observations, background information, or other credible claims. But if the stakes are high, it can be reasonable to hesitate. For example, if your doctor tells you that you have a cancerous tumor on your leg and wants to amputate the leg, you’d have a claim from a credible source that meets the other requirements for credibility. I trust, however, you’d get a second opinion before rolling up your pant leg. We will begin with sincerity and return to expertise in a moment.

We can have concerns about a person’s accuracy, objectivity, or truthfulness without suspecting him or her of evil intent. Generally people don’t lie to one another; given an absence of a specific reason to think otherwise, it is reasonable to assume a source speaks honestly and in good conscience. Of course, assuming that a source is honest does not require us to assume he or she cannot be mistaken. Even individuals operating in good conscience may still say things that are inaccurate, incomplete, or misleading. The key factors that need to be accounted for in assessing someone’s sincerity, besides the visual features we downplayed earlier, are character and coercion.

We can assess character in a couple of ways. First, if we are lucky enough to know the person well, then we may have insights into their sincerity. As with most behavior, sincerity is habit-forming, that is, those who have been caught lying before are more prone to lie again and may even be said to develop some skill at lying. I know that my wife is constantly trying to cheat when we play board games together. I simply expect her to cheat, and because she practices cheating so often, she is very hard to catch (and, if you are mentally condemning me for my distrust of wifey, just ask her…she will tell you that trying to get away with cheating is more fun than the game itself and the only reason she enjoys these games.) The second way is to note the role or vocation the person is in as they speak. If you are hearing the testimony of an actor on television, then you know that that is a role in which lying is the norm. We can take it a step farther. Certain professions, especially those high in coercion (we will discuss this next), are prone to insincerity. People who work in advertising, real estate, or law, among others, have gained a reputation for insincerity. It is wise to be skeptical of the things people in these roles say.

Coercion is found when a person has a lot to gain or lose by lying. The most simple case of coercion is when someone faces abuse if they don’t lie. Think of a mob movie where so and so will not testify out of fear. More common in our lives is where there is some positive incentive, and in our neurotic culture that means money, for lying. This is why we are rational to distrust the real estate agent or the auto mechanic. By telling lies that are easily disguised by special jargon, these individuals can gain a small fortune. It is not too hard to see why many criminals will give an insincere “not guilty” plea when the truth would land them years and years in prison (of course, this banks on our seriously flawed legal system; criminals in Japan or South Korea would be hard-pressed to lie in their plea). It doesn’t take much reflection to note that the most distrusted vocations are the ones where coercion gives the person the greatest incentive to lie: lawyers, auto mechanics, advertisers, real estate agents, or anyone working on behalf of a corporation for that matter.

If we do have suspicions about a source’s objectivity, accuracy, or truthfulness, the proper response is not to reject what he or she says as false. That would be overreacting, and is a mistake in reasoning (a fallacy). The appropriate response to concerns about the objectivity, accuracy, or veracity of a source is to suspend or reserve judgment on what the source says.

As to a source’s expertise, just as you cannot tell merely by looking at someone whether he or she is speaking truthfully, objectively, and accurately, you can't judge his or her knowledge or expertise by looking at mere surface features. A British-sounding scientist may appear more knowledgeable than a scientist who speaks, say, with a Texas drawl, but a person’s accent, gender, ethnicity, or clothing doesn't have much to do with a person’s knowledge. I started my teaching career at a large university in Southern California that had a very friendly and down-to-earth faculty. I can remember once when my wife and I ran into a couple of the university’s top scholars at the local movie plaza. My wife whispered to me, “It is hard to tell the difference between the philosophy professors and the people that live in the plaza” (i.e. homeless people). I mean, there may even be one or two people in the world who respect my knowledge a great deal, but you surely wouldn’t guess I am intelligent or well-educated by looking at my clothes or hygiene.

So then how do you judge a person’s expertise? Education and experience are often the most important factors, followed by accomplishments, reputation, and position, in no particular order. It is not always easy to evaluate the credentials of an expert, and credentials vary considerably from one field to another. For instance, don’t assume that the title “doctor” automatically demands respect. There are several doctorates that are easier than an A.A. degree and others are given away as promotions, such as to celebrities. Education includes but is not strictly limited to formal education - the possession of degrees from established institutions of learning.

Experience - both the kind and the amount - is an important factor in expertise. Experience is important if it is relevant to the issue at hand, but the mere fact that someone has been on the job for a long time does not automatically make him or her good at it. Accomplishments are an important indicator of someone’s expertise but, once again, only when those accomplishments are directly related to the question at hand. A Nobel Prize winner in physics is not necessarily qualified to speak publicly about toy safety, public school education (even in science), or nuclear proliferation, unless those are their specialties. A person’s reputation always exists only among a particular contingent of people. You may have a strong reputation as a pool player at your local billiards emporium, but that doesn’t necessarily put you in the same league as Minnesota Fats. Your friend may consider his friend Mr. Klein the greatest living expert on some particular subject, and he may be right. But you must ask yourself if your friend is in a position to evaluate Mr. Klein’s credentials. For instance, I might count as some kind of expert on U.S. foreign policy in a room full of apathetic Americans who get their news from entertainers (i.e. so-called “news” programs on television), but this does not make me as credible as Noam Chomsky, Greg Palast, or Robert Parry. By and large, the kind of reputation that counts most is the one a person has among other experts in his or her field.